Collatz Conjecture in Elm

Calculate the number of steps to reach 1 using the Collatz conjecture

Collatz Conjecture

The Collatz Conjecture or 3x+1 problem can be summarized as follows:

Take any positive integer n. If n is even, divide n by 2 to get n / 2. If n is
odd, multiply n by 3 and add 1 to get 3n + 1. Repeat the process indefinitely.
The conjecture states that no matter which number you start with, you will
always reach 1 eventually.

Given a number n, return the number of steps required to reach 1.

Examples

Starting with n = 12, the steps would be as follows:

12

6

3

10

5

16

8

4

2

1

Resulting in 9 steps. So for input n = 12, the return value would be 9.